Patent US3089978A successfully refreshed from Google Patents.
Patent US4559938A successfully refreshed from Google Patents.
US4559938A
Expired / Lapsed
US
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Adhesive dressing and components
Assignee: Smith and Nephew PLC
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Filing: 1982-08-11
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Granted: 1985-12-24
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Expires: 2002-08-11
Abstract
Abstract A flexible film suitable for use in adhesive medical dressings which film comprises a blend of polymers characterized in that the blend comprises a continuous matrix of 1,2 polybutadiene and an incompatible polymer which forms a discrete particulate phase within the continuous matrix and the film contains voids is described.
Inventors
- 👤 Peter J. Metcalfe
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 21:27
CPC Classifications
A; A61; A61F; A61F13/00; A61F13/02; A61F13/023; B; B32; B32B; B32B25/00; B32B25/02; A61L; A61L15/00; A61L15/16; A61L15/42; A61L15/58; B32B25/16; B32B3/00; B32B3/26; B32B3/266; B32B7/00; B32B7/04; B32B7/12; C; C08; C08J; C08J5/00; C08J5/18; C08L; C08L25/00; C08L25/02; C08L25/04; C08L25/06; C08L9/00; B32B38/00; B32B38/0012; B32B2038/0028; B32B2264/00; B32B2264/02; B32B2264/0214; B32B2264/0228; B32B2264/0235; B32B2270/00; B32B2405/00; B32B2535/00; C08J2309/00; C08L2205/00; C08L2205/14; C08L2205/18; Y; Y10; Y10T; Y10T428/00; Y10T428/249921; Y10T428/249953; Y10T428/249978
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
57 words
A flexible film suitable for use in adhesive medical dressings which film comprises a blend of polymers which comprises a continuous matrix of 1,2 polybutadiene and an incompatible polymer which forms a discrete particulate phase within the continuous matrix and the film contains voids whereby said voids provide means for moisture vapor transmission but not liquid permeability.
Claim 2
Dependent Claim
57 words
A flexible film suitable for use in adhesive medical dressings which film comprises a blend of polymers which comprises a continuous matrix of 1,2 polybutadiene and an incompatible polymer which forms a discrete particulate phase within the continuous matrix and the film contains voids whereby said voids provide means for moisture vapor transmission but not liquid permeability.
Claim 3
Dependent Claim
27 words
A film according to claim 1 which is 50 microns to 150 microns thick and in which the voids have a diameter of 3 to 20 microns.
Claim 4
Dependent Claim
13 words
A film according to claim 1 in which the incompatible polymer is polystyrene.
Claim 5
Dependent Claim
20 words
A film according to claim 1 in which the 1,2 polybutadiene comprises 45% to 80% by weight of the film.
Claim 6
Dependent Claim
30 words
A film according to claim 1 which is adapted to have a moisture vapour transmission rate of at least 200 g/m 2 /24 hours/37° C./100% to 10% relative humidity difference.
Claim 7
Dependent Claim
29 words
A film according to claim 1 which has apertures and has a moisture transmission rate of at least 500 g/m 2 /24 hours/37° C./100% to 10% relative humidity difference.
Claim 8
Dependent Claim
20 words
An adhesive medical dressing which comprises a flexible backing film of claim 1 on which is disposed an adhesive layer.
Claim 9
Dependent Claim
22 words
An adhesive medical dressing according to claim 7 in which the adhesive layer is a continuous layer of moisture vapour permeable adhesive.
Claim 10
Dependent Claim
15 words
An adhesive dressing according to claim 7 in sterile form and within a bacteria-proof package.
Claim 11
Dependent Claim
36 words
A process for preparing a flexible voided film according to claim 1 which comprises forming a film from a blend of 1,2 polybutadiene and an incompatible polymer and stretching the film until the voids are formed.
Claim 12
Dependent Claim
15 words
A film according to claim 1 wherein the 1,2 polybutadiene is a thermoplastic 1,2 polybutadiene.
Claim 13
Dependent Claim
35 words
A film according to claim 11 wherein the thermoplastic 1,2 polybutadiene contains a major amount of syndiotactic 1,2 polybutadiene having a crystallinity of 15% to 30% and an average molecular weight in excess of 100,000.
Claim 14
Dependent Claim
32 words
A film according to claim 1 wherein the particles of the discrete particulate phase of incompatible polymer are spherical or ellipsoidal in shape and have a diameter of at least 1 micron.
Claim 15
Dependent Claim
20 words
An adhesive medical dressing which comprises a flexible backing film of claim 11 on which is disposed an adhesive layer.
Claim 16
Dependent Claim
20 words
An adhesive medical dressing which comprises a flexible backing film of claim 12 on which is disposed an adhesive layer.
Claim 17
Dependent Claim
20 words
An adhesive medical dressing which comprises a flexible backing film of claim 13 on which is disposed an adhesive layer.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-12-23 | 1989-06-24 | 1989-12-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-12-23 | 1993-06-24 | 1993-12-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-12-23 | 1997-06-24 | 1997-12-24 | $7700.00 | Window Closed / Lapsed |